A scientist grows photosynthetic bacteria in transparent vessels at a constant temperature.
The scientist measures the rate of oxygen release at different light intensities and carbon dioxide concentrations.
| Relative light intensity | Rate of oxygen release at 0.04% carbon dioxide in cm3 h−1\text{cm}^3\ \text{h}^{-1}cm3 h−1 | Rate of oxygen release at 0.10% carbon dioxide in cm3 h−1\text{cm}^3\ \text{h}^{-1}cm3 h−1 |
|---|---|---|
| 20 | 4 | 4 |
| 40 | 8 | 8 |
| 80 | 12 | 16 |
| 160 | 12 | 24 |
Explain what these results show about the limiting factors at relative light intensities of 20 and 80.
Include a prediction of what would happen to the rate at a relative light intensity of 80 if the carbon dioxide concentration were increased above 0.10% while the other conditions remained unchanged.
117 exam-style questions on OCR GCSE Biology 1.4 Photosynthesis, covering 1.4.1 Photosynthesisers as biomass producers, 1.4.2 Factors affecting the rate of photosynthesis, and 1.4.3 Limiting factors in photosynthesis. Each one has a worked solution and a mark scheme showing where the marks go.